Removed fjagepy dependency on python 3.11

[notthetup]

The Self type from typing package in package in Python was introduced in Python 3.11. Since we don't really need it, removing it would allow fjagepy to run on older versions like Python 3.8 as well.

With that change, I rebuilt all the documentation. All files under docs/pydocs are just rebuilt by the documentation tool. They don't need to be reviewed.

Also updated pyproject.toml with more relevant meta-data.